<template>
  <el-breadcrumb 
    class="app-breadcrumb" 
    separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item 
        v-for="(item,index) in levelList" 
        :key="item.path">
        <span 
          v-if="item.redirect==='noredirect'||index==levelList.length-1" 
          class="no-redirect">{{
          generateTitle(item.meta.title) }}</span>
        <a 
          v-else 
          @click.prevent="handleLink(item)">{{ generateTitle(item.meta.title) }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script>
import { generateTitle } from '@/utils/i18n';
import pathToRegexp from 'path-to-regexp';

export default {
    data() {
        return {
            levelList: null
        };
    },
    watch: {
        $route() {
            this.getBreadcrumb();
        }
    },
    created() {
        this.getBreadcrumb();
    },
    methods: {
        generateTitle,
        getBreadcrumb() {
            let matched = this.$route.matched.filter(item => item.name);

            const first = matched[0];
            if (first && first.name.trim().toLocaleLowerCase() !== 'Dashboard'.toLocaleLowerCase()) {
                matched = [{ path: '/dashboard', meta: { title: 'dashboard' }}].concat(matched);
            }

            this.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false);
        },
        pathCompile(path) {
            // To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561
            const { params } = this.$route;
            var toPath = pathToRegexp.compile(path);
            return toPath(params);
        },
        handleLink(item) {
            const { redirect, path } = item;
            if (redirect) {
                this.$router.push(redirect);
                return;
            }
            this.$router.push(this.pathCompile(path));
        }
    }
};
</script>

<style rel="stylesheet/scss" lang="scss" scoped>
  .app-breadcrumb.el-breadcrumb {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin-left: 10px;
    .no-redirect {
      color: #97a8be;
      cursor: text;
    }
  }
</style>
